Mechanics

HEAD LIGHTS WON'T TURN OFF WHEN TRUCK IS TURNED OFF

1994 Mazda b3000 • 250,000 miles

The other day I made a couple of stops and when I returned home I had realized that my head lights would not shut off when I turned off my vehicle. In the interim I had disconnected the battery until I could begin troubleshooting the following day. First I had disconnected the wiring harness from the cab portion to see is the issue was in my cab but I had found that the problem was still there. Next I checked all the connections and grounds for corrosion that may be causing a faulty ground and all seems fine. Lastly, (should've been my first place to look) I examined the fuse box and was able to disengage the lights by removing the 15A fuse. After some continuity testing, I am suspecting the starter relay found between the battery and the fuse box. I have no idea how to test this relay and I as suspecting that the relay is permanently fused in an "on" state and therefore won't disengage once the power has been removed. Before I go and purchase a replacement starter relay I am inquiring as to whether or not my suspicions are accurate. Please advise and thank you in advance for any assistance.

Regards
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CJulian
May 4, 2012.




U need to remove the head light switch. If u disconnect it and the lights should go off. Replace the switch. If not their is a short to power. Start here

Cadieman
May 4, 2012.
I believe the headlight relay is stuck in the on position. Try swapping the relay with another to see if the problem goes away.

KHLow2008
May 4, 2012.
Do you have day time running lamps

Djcl
May 4, 2012.
The head light switch can do that

Djcl
May 4, 2012.
Well I guess I should've mentioned that I had already isolated the interior switch as noth being the issue. I have now replaced the starter relay and the problem is still there. Now I have disconnected the main power cable to the fuse box from the starter relay and the lights go out so I am to believe that the issue is now withing the fuse box or the main disconnect from the fuse box to the starter relay. Any further advice? Thanks for all the previous responses thus far.

Regards.

Tiny
CJulian
May 4, 2012.
Yes I do have daytime running lights
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Tiny
CJulian
May 4, 2012.
There is a photo cell under the defroster grid that tells the cpu. Wheather it day or night. When u cover it the day runninglites will shut off. When u uncover it. The day time lights will come back

Cadieman
May 4, 2012.

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